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9ce4ac64b2
Various fmax and fmin function implementations mishandle sNaN arguments: (a) When both arguments are NaNs, the return value should be a qNaN, but sometimes it is an sNaN if at least one argument is an sNaN. (b) Under TS 18661-1 semantics, if either argument is an sNaN then the result should be a qNaN (whereas if one argument is a qNaN and the other is not a NaN, the result should be the non-NaN argument). Various implementations treat sNaNs like qNaNs here. This patch fixes the powerpc versions of these functions (shared by float and double, 32-bit and 64-bit). The structure of those versions is that all ordered cases are already handled before anything dealing with the case where the arguments are unordered; thus, this patch causes no change to the code executed in the common case (neither argument a NaN). Tested for powerpc (32-bit and 64-bit), together with tests to be added along with the x86_64 / x86 fixes. [BZ #20947] * sysdeps/powerpc/fpu/s_fmax.S (__fmax): Add the arguments when either is a signaling NaN. * sysdeps/powerpc/fpu/s_fmin.S (__fmin): Likewise.
78 lines
2.1 KiB
ArmAsm
78 lines
2.1 KiB
ArmAsm
/* Floating-point minimum. PowerPC version.
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Copyright (C) 1997-2016 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<http://www.gnu.org/licenses/>. */
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#include <sysdep.h>
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ENTRY(__fmin)
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/* double [f1] fmin (double [f1] x, double [f2] y); */
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fcmpu cr0,fp1,fp2
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bgt cr0,0f /* if x > y, neither x nor y can be NaN... */
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bnulr+ cr0
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/* x and y are unordered, so one of x or y must be a NaN... */
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fcmpu cr1,fp2,fp2
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bun cr1,1f
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/* x is a NaN; y is not. Test if x is signaling. */
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#ifdef __powerpc64__
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stfd fp1,-8(r1)
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lwz r3,-8+HIWORD(r1)
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#else
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stwu r1,-16(r1)
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cfi_adjust_cfa_offset (16)
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stfd fp1,8(r1)
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lwz r3,8+HIWORD(r1)
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addi r1,r1,16
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cfi_adjust_cfa_offset (-16)
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#endif
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andis. r3,r3,8
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bne cr0,0f
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b 2f
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1: /* y is a NaN; x may or may not be. */
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fcmpu cr1,fp1,fp1
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bun cr1,2f
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/* y is a NaN; x is not. Test if y is signaling. */
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#ifdef __powerpc64__
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stfd fp2,-8(r1)
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lwz r3,-8+HIWORD(r1)
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#else
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stwu r1,-16(r1)
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cfi_adjust_cfa_offset (16)
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stfd fp2,8(r1)
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lwz r3,8+HIWORD(r1)
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addi r1,r1,16
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cfi_adjust_cfa_offset (-16)
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#endif
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andis. r3,r3,8
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bnelr cr0
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2: /* x and y are NaNs, or one is a signaling NaN. */
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fadd fp1,fp1,fp2
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blr
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0: fmr fp1,fp2
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blr
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END(__fmin)
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weak_alias (__fmin,fmin)
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/* It turns out that it's safe to use this code even for single-precision. */
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strong_alias(__fmin,__fminf)
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weak_alias (__fmin,fminf)
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#ifdef NO_LONG_DOUBLE
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weak_alias (__fmin,__fminl)
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weak_alias (__fmin,fminl)
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#endif
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